Surgical robot, control method, system and readable storage medium

Abstract

The present invention provides a surgical robot, a control method, a system and a readable storage medium. The surgical robot includes a manipulation terminal. The control method of the surgical robot includes: setting a safety zone and a warning boundary outside the safety zone based on edge information of the surgical object; based on a distance function between the current posture of the manipulation terminal and the warning boundary, combined with first feedback information fed back by the manipulation terminal and second feedback information generated based on external environmental forces, compensating the driving information applied by the surgical robot to the manipulation terminal, so that after the manipulation terminal exceeds the range of the safety zone, the driving influence of the external environmental force on the manipulation terminal is reduced, eliminated or limited.

Description

[0001] This case is a divisional application of the Chinese patent application with application number: 202011223748.X, invention title: Surgical robot, control method, system and readable storage medium Technical Field

[0002] The present invention relates to the field of robot-assisted surgery systems and methods, and in particular to a surgical robot, a control method, a system and a readable storage medium. Background Art

[0003] Orthopedic surgical robots can effectively reduce damage to soft and bone tissue, resulting in less bleeding and trauma for patients, which is more conducive to postoperative knee joint recovery. However, during conventional robotic surgery, the surgeon still relies on the surgeon to control the extent of the osteotomy. This results in varying outcomes for each surgeon, leading to varying outcomes for each patient. There is even the possibility of intraoperative errors, resulting in excessive removal of soft and bone tissue.

[0004] Therefore, it is necessary to constrain the osteotomy boundaries of orthopedic surgical robots to effectively limit their movement within these boundaries. Although design solutions exist to constrain the robot's movement boundaries, such solutions require a precise dynamic model of the tactile device, which is difficult to implement for surgical robots with complex mechanisms. This is especially true when nonlinear factors such as friction are involved, which can easily lead to misjudgment by the surgeon. Summary of the Invention

[0005] The purpose of the present invention is to provide a surgical robot, a control method, a system and a readable storage medium to solve the problems of difficult and inaccurate boundary control of existing surgical robots and easy misoperation.

[0006] To solve the above technical problems, according to a first aspect of the present invention, a control method for a surgical robot is provided. The surgical robot includes a manipulation end. The control method for the surgical robot includes:

[0007] Setting a safety zone and a warning boundary outside the safety zone according to edge information of the surgical object;

[0008] Based on the distance function between the current posture of the manipulation end and the warning boundary, combined with the first feedback information fed back by the manipulation end and the second feedback information generated based on the external environmental force, the driving information applied by the surgical robot to the manipulation end is compensated so that after the manipulation end exceeds the range of the safety zone, the driving influence of the external environmental force on the manipulation end is reduced, eliminated or limited.

[0009] Optionally, the first feedback information includes command posture information of the joint of the manipulation end, and the second feedback information includes torque information generated by the external environmental force on the joint of the manipulation end.

[0010] Optionally, the step of compensating the driving information applied by the surgical robot to the manipulation end comprises:

[0011] Obtaining a command angle θ of the joint of the manipulator terminal through kinematic inverse solution according to the command posture information Xd;

[0012] The command angle θ is used as the input of the dynamic calculation to calculate the theoretical output torque Fs;

[0013] The command angle θ is used as the input of the posture controller to calculate the torque required for the joint of the manipulator end to move from the current posture to the command posture;

[0014] The external environmental force torque Fc is calculated based on the equivalent torque F sensed by the force sensor under the external environmental force, the gravity compensation and friction compensation torque N, and the theoretical output torque Fs;

[0015] The external environmental force Fc is compensated to the torque required for the joint of the manipulation end to move from the current posture to the command posture to obtain the driving information.

[0016] Optionally, the external environmental force includes: the resistance torque Fa generated by the surgical object on the manipulation end, and the traction torque f applied by the operator to the manipulation end; the equivalent torque F satisfies: F = Fs + N + Fa + f; the external environmental force torque Fc satisfies: Fc = F-Fs-N.

[0017] Optionally, the calculation step of the posture controller includes:

[0018] The torque required for the joint of the manipulation end to move from the current posture to the command posture is calculated based on the command posture and the current posture of the joint of the manipulation end, as well as the command speed and the current speed.

[0019] Optionally, the command speed is calculated by command posture difference.

[0020] Optionally, the first feedback information includes command posture information of the joint of the manipulation end, and the first feedback information includes an impedance control model of the joint of the manipulation end caused by the external environmental force.

[0021] Optionally, the step of compensating the driving information applied by the surgical robot to the manipulation end comprises:

[0022] Obtaining a command angle θ of the joint of the manipulator terminal through kinematic inverse solution according to the command posture information Xd;

[0023] The command angle θ is used as the input of the dynamic calculation to calculate the theoretical output torque Fs;

[0024] Based on the posture difference between the current posture of the manipulator terminal and the command posture, and the speed difference between the current speed of the manipulator terminal and the command speed, a first torque in Cartesian space is calculated according to the impedance control model;

[0025] Transform the first moment into the second moment acting on each joint according to the transformation of the Jacobian matrix at the current joint angle;

[0026] Feeding forward the corresponding friction force f to compensate each joint of the manipulator end to obtain the third torque of each joint;

[0027] The driving information is obtained based on the theoretical output torque Fs, the third torque, and the second torque.

[0028] Optionally, the input of the impedance control model includes the following steps:

[0029] According to the equivalent moment F output by the force sensor under the action of the external environmental force, the position change corresponding to the joint is calculated according to the admittance control;

[0030] Based on the posture change, a posture difference between the actual posture of the manipulator terminal and the command posture is calculated by kinematic forward solution;

[0031] The posture difference is used as input to the impedance control model.

[0032] Optionally, the manipulation end includes a robotic arm and / or a manipulator, and the first feedback information includes command posture information of the joints of the robotic arm and / or the manipulator, and the manipulator is used to fix and guide surgical instruments to perform surgical operations.

[0033] In order to solve the above technical problems, according to a second aspect of the present invention, a readable storage medium is further provided, on which a program is stored, and when the program is executed, the control method of the surgical robot as described above is implemented.

[0034] In order to solve the above technical problems, according to the third aspect of the present invention, a surgical robot is also provided, which includes a manipulation end, the manipulation end including a robotic arm and / or a manipulator for guiding surgical instruments to perform surgical operations, and the manipulation end is controlled using the control method of the surgical robot as described above.

[0035] In order to solve the above technical problems, according to the fourth aspect of the present invention, a surgical robot system is also provided, which includes a control device, a navigation device and a manipulation end, the navigation device is used to track the current posture of the manipulation end and feed back the posture information to the control device, and the control device is used to control the manipulation end according to the method described above.

[0036] Optionally, the manipulation end includes a robotic arm and a manipulator for guiding surgical instruments to perform surgical operations, the manipulator has multiple degrees of freedom, and the first feedback information includes command posture information of the joints of the robotic arm and / or the manipulator.

[0037] To summarize, in the surgical robot, control method, system and readable storage medium provided by the present invention, the surgical robot includes a manipulation end, and the control method of the surgical robot includes: setting a safety zone and a warning boundary outside the safety zone based on the edge information of the surgical object; based on the distance function between the current posture of the manipulation end and the warning boundary, combined with the first feedback information fed back by the manipulation end and the second feedback information generated based on the external environmental force, compensating the driving information applied by the surgical robot to the manipulation end, so that after the manipulation end exceeds the range of the safety zone, the driving influence of the external environmental force on the manipulation end is reduced, eliminated or limited.

[0038] With such a configuration, by compensating the first feedback information and the second feedback information into the driving information applied to the manipulation end, the external environmental force is reversely compensated to the driving joint, thereby achieving boundary control, which can allow the external environmental force to act on the patient as little as possible. When the manipulation end exceeds the range of the safety zone, the greater the additional driving torque required to drive the robotic arm joint, the greater the required external environmental force, thereby achieving the effect of avoiding operator misoperation. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Those skilled in the art will appreciate that the accompanying drawings are provided for a better understanding of the present invention and do not constitute any limitation on the scope of the present invention.

[0040] Figure 1 is a schematic diagram of a surgical scene involved in the present invention;

[0041] Figure 2 Schematic diagram of the degrees of freedom of the osteotomy guide tool according to the first embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of an osteotomy guide tool according to a first embodiment of the present invention;

[0043] Figure 4 is a schematic diagram of a surgical robot according to a first embodiment of the present invention;

[0044] Figure 5 This is a principle block diagram of a control method according to a first embodiment of the present invention;

[0045] Figure 6 This is a principle block diagram of a control method according to a second embodiment of the present invention;

[0046] Figure 7 is a schematic diagram of an impedance control physical model according to a second embodiment of the present invention;

[0047] Figure 8 is a schematic diagram of impedance control according to the second embodiment of the present invention;

[0048] Figure 9 This is a schematic diagram of the admittance control principle of the second embodiment of the present invention.

[0049] In the attached figure:

[0050] 1- Operating trolley; 2- Robotic arm; 3- Tool target; 4- Osteotomy guide tool; 5- Osteotomy tool; 6- Tracker; 7- Auxiliary display; 8- Main display; 9- Navigation trolley; 10- Keyboard; 11- Femoral target; 12- Femur; 13- Tibia target; 14- Tibia; 15- Base target; 16- X-axis; 17- Y-axis; 18- Z-axis. DETAILED DESCRIPTION

[0051] To make the objects, advantages, and features of the present invention more clearly apparent, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale. They are only used to conveniently and clearly assist in illustrating the purposes of the embodiments of the present invention. In addition, the structures shown in the drawings are often part of the actual structure. In particular, different drawings may need to illustrate different focuses and sometimes use different scales.

[0052] As used in the present invention, the singular forms "a", "an", and "the" include plural objects, the term "or" is generally used to include the meaning of "and / or", the term "several" is generally used to include the meaning of "at least one", and the term "at least two" is generally used to include the meaning of "two or more". In addition, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first", "second", and "third" may explicitly or implicitly include one or at least two of the features. The term "proximal end" generally refers to the end closest to the operator, and the term "distal end" generally refers to the end closest to the patient, that is, the surgical object. "One end" and "the other end" as well as "proximal end" and "distal end" generally refer to corresponding two parts, which include not only the endpoints, unless the content clearly indicates otherwise. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0053] The core concept of the present invention is to provide a surgical robot, control method, system, and readable storage medium to address the problems of difficult and inaccurate boundary control and prone to misoperation of existing surgical robots. The following description is made with reference to the accompanying drawings.

[0054] Figure 1 An exemplary embodiment is shown, illustrating the application scenario of a surgical robot for knee replacement. However, the surgical robot of the present invention is not particularly limited to the application environment and can also be used for other surgeries, such as surgeries on the limbs, abdomen, chest, and brain. The following description uses the surgical robot for knee replacement as an example, but this should not be construed as a limitation of the present invention.

[0055] like Figure 1 As shown, the surgical robot system includes a control device, a navigation device, a robotic arm 2 and an osteotomy guide tool 4. The robotic arm 2 is arranged on the operating trolley 1. The control device is a computer in some embodiments, but the present invention is not limited to this. The computer is equipped with a processor, a main display 8 and a keyboard 10, and more preferably also includes an auxiliary display 7. The contents displayed by the auxiliary display 7 and the main display 8 can be the same or different. The navigation device can be a magnetic positioning navigation device, an optical positioning navigation device / optical positioning sensor or an inertial positioning navigation device. Preferably, the navigation device is an optical positioning navigation device, which has high measurement accuracy compared to other navigation methods and can effectively improve the positioning accuracy of the osteotomy guide tool 4. In the following description, the optical positioning navigation device is used as an example for illustration, but is not limited to this.

[0056] The navigation device specifically includes a navigation marker and a tracker 6. The navigation marker includes a base target 15 and a tool target 3. The base target 15 is fixed, for example, the base target 15 is fixed to the operating table 1 and is used to provide a base coordinate system (or base target coordinate system), while the tool target 3 is mounted on the osteotomy guide tool 4 and is used to track the position of the osteotomy guide tool 4. The osteotomy guide tool 4 is mounted on the end of the robotic arm 2, so that the robotic arm 2 supports the osteotomy guide tool 4 and adjusts the spatial position and posture of the osteotomy guide tool 4.

[0057] In practice, a tracker 6 is used to capture the signal reflected by the tool target 3 (preferably an optical signal from the tracker 6) and record the posture of the tool target 3 (i.e., the position and posture of the tool target 3 in the base coordinate system). The computer program stored in the memory of the control device then controls the movement of the robotic arm 2 according to the current posture and expected posture of the tool target 3. The robotic arm 2 drives the osteotomy guide tool 4 and the tool target 3 to move and make the tool target 3 reach the expected posture. The expected posture of the tool target 3 corresponds to the expected posture of the osteotomy guide tool 4.

[0058] Therefore, for the application of surgical robots, the automatic positioning of the osteotomy guide tool 4 can be achieved, and during the operation, the tool target 3 tracks and feeds back the real-time posture of the osteotomy guide tool 4, and the position and posture of the osteotomy guide tool 4 can be adjusted by controlling the movement of the robotic arm 2. The surgical instruments (such as an oscillating saw or an electric drill) installed on the osteotomy guide tool 4 can be further controlled. Not only is the positioning accuracy of the osteotomy guide tool 4 high, but the osteotomy guide tool 4 is also supported by the robotic arm 2 without the need to fix the guide tool on the human body, which can avoid damage to the human body.

[0059] Typically, the surgical robot also includes an operating trolley 1 and a navigation trolley 9. The control device and a portion of the navigation system are mounted on the navigation trolley 9. For example, the processor is mounted inside the navigation trolley 9, while the keyboard 10 is placed outside the navigation trolley for operation. The main display 8, auxiliary display 7, and tracker 6 are all mounted on a bracket vertically fixed to the navigation trolley 9. The robotic arm 2 is mounted on the operating trolley 1. The use of the operating trolley 1 and navigation trolley 9 makes the entire surgical procedure more convenient.

[0060] When performing knee replacement surgery, the use of the surgical robot in this embodiment generally includes the following operations:

[0061] Step SK1: Move the operating trolley 1 and the navigation trolley 9 to a suitable position next to the bed;

[0062] Step SK2: installing navigation markers (the navigation markers also include the femoral target 11 and the tibial target 13), the osteotomy guide tool 4, and other related components (such as a sterile bag);

[0063] Step SK3: Preoperative planning. Specifically, the operator imports the patient's bone CT / MRI scan model into the computer for preoperative planning to obtain an osteotomy plan. The osteotomy plan includes, for example, information such as the coordinates of the osteotomy plane, the model of the prosthesis, and the installation orientation of the prosthesis. Specifically, a three-dimensional virtual model of the knee joint is created based on the patient's knee joint image data obtained by the CT / MRI scan. Then, an osteotomy plan is created based on the three-dimensional virtual model of the knee joint, so that the operator can perform a preoperative evaluation based on the osteotomy plan. More specifically, the osteotomy plan is determined based on the three-dimensional virtual model of the knee joint in combination with the obtained prosthesis size specifications and the installation position of the osteotomy plate. The osteotomy plan is ultimately output in the form of a surgical report, which records a series of reference data such as the coordinates of the osteotomy plane, the osteotomy amount, the osteotomy angle, the prosthesis specifications, the installation position of the prosthesis, and surgical auxiliary tools. In particular, it also includes a series of theoretical explanations, such as the reasons for selecting the osteotomy angle, to provide a reference for the operator. The three-dimensional virtual model of the knee joint can be displayed on the main display 8, and the operator can input surgical parameters through the keyboard 10 for preoperative planning.

[0064] Step SK4: Real-time bone registration; In this embodiment, the navigation markers also include a femoral target 11 and a tibial target 13. The femoral target 11 is used to locate the spatial position and posture of the femur 12, and the tibial target 13 is used to locate the spatial position and posture of the tibia 14. After the preoperative evaluation, the positions of the bone feature points need to be acquired in real time. Only then can the processor use the feature matching algorithm to obtain the actual position / posture of the femur 12 and tibia 14 and correspond it to the image position of the femur 12 and tibia 14. The navigation device then links the actual position of the femur 12 and tibia 14 with the corresponding targets mounted on the femur 12 and tibia 14, allowing the femoral target 11 and tibial target 13 to track the actual position of the bones in real time. The actual positions of the femur 12 and tibia 14 are linked to corresponding targets mounted on the femur 12 and tibia 14 through a navigation device, so that the femoral target 11 and the tibial target 13 can track the actual positions of the bones in real time. During the operation, as long as the relative positions between the targets and the bones are fixed, bone movement will not affect the surgical results.

[0065] Step SK5: Drive the robotic arm 2 to the predetermined position and perform the surgical procedure. Specifically, the navigation device transmits the coordinates of the pre-planned osteotomy plane to the robotic arm 2. The robotic arm 2 locates the osteotomy plane using the tool target 3 and moves to the predetermined position. The robotic arm 2 then enters a hold state (i.e., remains stationary). The operator then uses an osteotomy tool 5, such as an oscillating saw or electric drill, guided, fixed, or positioned by the osteotomy guide tool 4 to perform osteotomy and / or drilling. After completing the osteotomy and drilling procedures, the operator can then install the prosthesis and perform other surgical procedures.

[0066] Traditional surgical procedures and navigational surgical systems without a robotic arm require manual adjustment and positioning of the osteotomy guide tool, resulting in poor precision and inefficient adjustment. However, using the robotic arm 2 to position the osteotomy guide tool 4 eliminates the need for additional bone screws to secure the osteotomy guide tool to the bone, reducing the patient's trauma and shortening surgical time. As previously mentioned, the tool target 3 can be mounted on the osteotomy guide tool 4. However, in other embodiments, the tool target 3 can also be mounted on the distal joint of the robotic arm 2.

[0067] The above-described surgical robot can be used to perform robot-assisted surgery, helping the operator locate the site or osteotomy tool to be cut, thereby facilitating osteotomy. However, during osteotomy, for example, after the robot arm 2 enters the hold state, it is difficult for the operator to constrain the position of the osteotomy guide tool 4 to prevent the influence of external environmental forces on the position of the osteotomy guide tool 4. Furthermore, the range of motion of the osteotomy guide tool 4 cannot be effectively limited to a certain boundary range, which may result in unnecessary harm to the patient if the operator misoperates.

[0068] Based on this, an embodiment of the present invention provides a control method for a surgical robot, wherein the surgical robot includes a manipulation terminal. It should be understood that the manipulation terminal includes at least one of a robotic arm 2 and a manipulator (used to guide surgical instruments to perform surgical operations, such as an osteotomy guide tool 4), or a combination of the two. The control method of the surgical robot is used to control the movement of the manipulation terminal. In some other application scenarios, the manipulator is not limited to the osteotomy guide tool 4, but is also applicable to other occasions where there are boundary restrictions on the range of motion of the manipulation terminal of the surgical robot. The surgical robot is controlled using the control method.

[0069] [Example 1]

[0070] Please refer to Figures 2 to 5 ,in, Figure 2 Schematic diagram of the degrees of freedom of the osteotomy guide tool according to the first embodiment of the present invention; Figure 3 is a schematic diagram of an osteotomy guide tool according to a first embodiment of the present invention; Figure 4 is a top view of the osteotomy guide tool according to embodiment 1 of the present invention; Figure 4is a schematic diagram of a surgical robot according to a first embodiment of the present invention; Figure 5 This is a principle block diagram of the control method of the first embodiment of the present invention.

[0071] The first embodiment is described by taking an osteotomy guide tool 4 as an example of a manipulation end. In practice, the osteotomy guide tool and / or the joints of the robotic arm may also be controlled. Figures 2 to 3 An osteotomy guide tool 4 is shown, which includes three degrees of freedom, namely Figure 2 The degrees of freedom shown are translation along the X axis, translation along the Y axis, and rotation around the Z axis. For details, please refer to Figure 3 , which is a top view of the osteotomy guide tool 4. The osteotomy guide tool 4 includes an X-axis 16, a Y-axis 17, and a Z-axis 18 perpendicular to the X-axis 16 and Y-axis 17. After being mounted on the osteotomy guide tool 4, the osteotomy tool 5 (such as an oscillating saw) can translate along the X-axis 16 and the Y-axis 17, respectively. The osteotomy tool 5 can also rotate about the Z-axis 18. The X-axis 16, the Y-axis 17, and the Z-axis 18 can be considered to correspond to the three joints of the osteotomy guide tool 4. Preferably, each of these three joints can receive drive information from the control device and perform actions based on the drive information. For example, the osteotomy guide tool 4 includes three joint drive motors to correspond to three degrees of freedom. In other embodiments, the manipulation end can also be a robotic arm 2, which also includes several joint drive motors. Of course, in some embodiments, the manipulation end can also include the robotic arm 2 and the osteotomy guide tool 4.

[0072] For further information, please refer to Figure 4 The tracker 6 can identify the spatial position of the current osteotomy tool 5 through the base target 15. Specifically, assuming that the robot arm 2 is fixed at a certain position (that is, the robot arm enters the holding state and is fixed at a certain position), its position under the tracker 6 is (This posture is the posture information obtained by the control device first according to the joint encoder in the robot arm, and then the posture information is converted by the matrix to obtain the posture of the robot arm under the tracker). The posture of the osteotomy guide tool 4 under the tracker 6 is (This posture is calculated by tracking the tool target 3 on the osteotomy guide tool 4 by the tracker 6), then the robot arm 2 is stationary, and the osteotomy guide tool 4 moves alone to adjust the posture of the osteotomy tool 5 for:

[0073]

[0074] It can be understood that the position of the osteotomy guide tool 4 can be tracked and obtained by the tracker 6. Since the osteotomy tool 5 is mounted on the osteotomy guide tool 4, the position of the osteotomy guide tool 4 reflects the spatial position of the osteotomy tool 5.

[0075] The control method of the surgical robot includes:

[0076] Step S1: setting a safety zone and a warning boundary outside the safety zone according to edge information of the surgical object;

[0077] Step S2: Based on the distance function between the current posture of the surgical instrument (such as the osteotomy tool 5) installed on the manipulation end (such as the osteotomy guide tool 4) and the warning boundary, combined with the first feedback information fed back by the manipulation end and the second feedback information generated based on the external environmental force, the driving information applied by the surgical robot to the manipulation end is compensated so that the driving influence of the external environmental force on the manipulation end is reduced, eliminated or limited after the manipulation end exceeds the range of the safety zone.

[0078] In an exemplary embodiment, taking bones as the surgical object as an example, in step S1, it is first necessary to set a safety zone and a warning boundary. For example, in some embodiments, the edge information of the bones can be obtained by an image acquisition device (such as a CT scanning device), and the safety zone and the warning boundary are set based on the edge information of the bones. Specifically, the environmental boundary of the bones is acquired by the image acquisition device, and then the operator (such as a doctor) sets the preoperative plan based on experience, and sets the warning boundary and the safety zone based on the environmental boundary (starting from the bones, from the inside to the outside, it is safety zone-environmental boundary-warning boundary, where the safety zone is located at the innermost and belongs to the safe operation area of the surgery).

[0079] In step S2, the first feedback information includes the command posture information of the joints of the robotic arm 2 and / or the osteotomy guide tool 4, and the second feedback information includes the torque information applied to the osteotomy guide tool 4 calculated by the force generated by the external environmental force on the joints of the robotic arm 2 and / or the osteotomy guide tool 4.

[0080] In this embodiment, based on the distance function between the current position of the osteotomy guide tool 4 (which can be obtained by the tracker 6 tracking the position of the osteotomy guide tool 4) and the warning boundary, combined with the position information of the joints of the robotic arm 2 and / or the osteotomy guide tool 4 and the torque information generated by the external environmental force on the osteotomy guide tool 4, a torque compensation control mode is used to compensate the drive information applied to the osteotomy guide tool 4 by the control device, so that the external environmental force is minimized or not applied to the bone. Optionally, the warning boundary includes a warning line or a warning surface, etc. Those skilled in the art can establish a distance function between the current position of the osteotomy guide tool 4 and the warning boundary based on existing technology. In a specific implementation, the osteotomy guide tool 4 can be moved in a certain direction into the safe zone and stopped, and then the distance function can be established. The osteotomy guide tool 4 has three joints with three degrees of freedom, that is, it adds three additional degrees of freedom of movement on the basis of the multiple joints of the robotic arm 2. For example, if the robotic arm 2 has 6 degrees of freedom, then the robotic arm 2 and the osteotomy guide tool 4 have a total of 9 degrees of freedom of movement, which significantly improves the flexibility of surgical operations.

[0081] Optionally, the external environmental force includes: the resistance generated by the surgical object (such as a bone) on the manipulation end (such as the osteotomy guide tool 4), and the traction force applied by the operator to the osteotomy guide tool 4. Specifically, the traction force applied by the operator to the osteotomy guide tool 4 can be a push or pull force of the human hand.

[0082] The external environmental force can be measured and output as an equivalent torque F by the force sensor 304. The force sensor 304 includes, but is not limited to, a six-dimensional force sensor or a joint torque sensor, which can be mounted on the osteotomy guide tool 4. The force sensor 304 can measure the operator's traction force on the osteotomy guide tool 4 and the resistance of the bone to the osteotomy guide tool 4 through the osteotomy tool 5. Of course, the external environmental force can also be the equivalent torque F obtained by the current of the joint drive motor of the osteotomy guide tool 4.

[0083] Please refer to Figure 5 The step of compensating the driving information applied by the surgical robot to the osteotomy guide tool 4 includes:

[0084] Step SA1: Obtain the command angle θ of the joint of the osteotomy guide tool 4 through kinematic inverse solution 301 based on the command posture information Xd; the command posture refers to the target posture sent by the control system of the surgical robot to the osteotomy guide tool 4, and the command angle θ refers to the target angle sent by the control system of the surgical robot to the joint of the osteotomy guide tool 4.

[0085] Step SA2: The command angle θ is used as input to the dynamics calculation 305 to calculate the theoretical output torque Fs. Specifically, the command angle θ can be decomposed into the command position and command velocity of the joint of the osteotomy guide tool 4. The command position and command velocity of the joint are used to calculate the theoretical output torque Fs of the joint of the osteotomy guide tool 4 based on the dynamics calculation 305.

[0086] Step SA3: Using the command angle θ as input to the posture controller 302, the torque required for the joints of the osteotomy guide tool 4 to move from their current posture to the command posture (i.e., target posture) is calculated. Furthermore, the posture controller 302 includes calculating the torque required for the joints of the osteotomy guide tool 4 to move from their current posture to the command posture based on the command posture and current posture of the joints of the osteotomy guide tool 4, as well as the command speed and current speed. Preferably, the command speed is calculated by differentially calculating the command posture.

[0087] Step SA4: Calculate the external environmental force torque Fc (see Figure 5 (See reference numeral 306). The external environmental force torque Fc here can be understood as the combined torque of the operator's traction torque f on the osteotomy guide tool 4 and the resistance torque Fa exerted by the bone on the osteotomy guide tool 4 via the osteotomy tool 5. Optionally, the equivalent torque F satisfies: F = Fs + N + Fa + f; and the external environmental force torque Fc satisfies: Fc = F - Fs - N. Furthermore, after calculating the external environmental force torque Fc, it is processed by a force controller 307 to ensure that the calculated theoretical external environmental force torque Fc is more consistent with the actual value.

[0088] Step SA5: Compensate the external environmental force torque Fc to the torque required for the joint of the osteotomy guide tool 4 to move from the current posture to the command posture (see Figure 5 308), obtain the driving information to realize the control of the manipulator end (see Figure 5In the reference number 303). Specifically, the joint torque to be compensated is calculated according to the distance function and compensated to each joint of the osteotomy guide tool 4, thereby obtaining the driving information of each joint. When the osteotomy guide tool 4 reaches the warning boundary, the system will automatically increase the resistance generated by each joint to resist the traction force of the operator, so as to make the traction force applied by the operator act on the osteotomy surface as little as possible to achieve a protective effect. Optionally, during the operation, the osteotomy guide tool 4 works normally in the safety zone; if the osteotomy guide tool 4 crosses the safety boundary, it can move at a limited speed; when it reaches the warning boundary, the system executes according to the distance function to control the osteotomy guide tool 4 to move along the warning boundary or stop on the warning boundary. In this way, the purpose of reducing the driving influence of the external environmental force on the osteotomy guide tool 4 after the osteotomy guide tool 4 exceeds the range of the safety zone is achieved.

[0089] This embodiment also provides a readable storage medium on which a program is stored. When the program is executed, the control method described above is implemented. The readable storage medium can be integrated into the surgical robot, such as integrated into the control device, or can be attached independently.

[0090] Furthermore, this embodiment also provides a surgical robot system, which includes a control device, a navigation device, and a manipulation terminal, wherein the navigation device is used to track the current posture of the manipulation terminal and feed back the posture information to the control device, and the control device is used to control the manipulation terminal according to the method described above. Preferably, in the surgical robot system, the manipulation terminal includes a robotic arm and a manipulator for guiding surgical instruments to perform surgical operations, the manipulator having multiple degrees of freedom, and the first feedback information includes command posture information of the joints of the robotic arm and / or the manipulator.

[0091] In summary, by compensating the first feedback information and the second feedback information into the driving information applied to the manipulation end, the external environmental force is reversely compensated to the driving joint, thereby achieving boundary control, which can allow the external environmental force to act on the patient as little as possible. When the manipulation end exceeds the range of the safety zone, the greater the external environmental force required, the more effective it is to avoid operator misoperation.

[0092] [Example 2]

[0093] Please refer to Figures 6 to 9 ,in, Figure 6 This is a principle block diagram of a control method according to a second embodiment of the present invention; Figure 7 is a schematic diagram of an impedance control physical model according to a second embodiment of the present invention; Figure 8 is a schematic diagram of impedance control according to the second embodiment of the present invention; Figure 9 This is a schematic diagram of the admittance control principle of the second embodiment of the present invention.

[0094] The surgical robot, control method, system and readable storage medium provided in the second embodiment of the present invention are basically the same as the surgical robot, control method, system and readable storage medium of the surgical robot provided in the first embodiment. The same parts will not be described again, and only the differences will be described below.

[0095] The control method provided in Example 2 primarily employs an impedance control mode to compensate for the traction force applied by the operator. Specifically, in step S2, the first feedback information includes: commanded position information of the joints of the manipulator terminal; and the second feedback information includes an impedance control model of the joints of the manipulator terminal due to the external environmental force.

[0096] The second embodiment also uses bones as the surgical object and the osteotomy guide tool 4 as the manipulation end for example.

[0097] Please refer to Figure 6 The step of compensating the driving information applied by the surgical robot to the osteotomy guide tool 4 includes:

[0098] Step SB1: Obtain the command angle θ of the joint of the osteotomy guide tool 4 through kinematic inverse solution 301 according to the command posture information Xd.

[0099] Step SB2: The command angle θ is used as the input of the dynamics calculation 305 to calculate the theoretical output torque Fs. The meaning and solution process of the command angle θ and the theoretical output torque Fs can be referred to steps SA1 and SA2 of the first embodiment.

[0100] Step SB3: Based on the posture difference between the current posture of the osteotomy guide tool 4 and the command posture, and the speed difference between the current speed of the osteotomy guide tool 4 and the command speed, a first torque in Cartesian space is calculated according to the impedance control model 312. This first torque can be understood as a calculated virtual torque in Cartesian space.

[0101] Step SB4: The first moment is converted into the transpose J of the Jacobian matrix at the current joint angle. T Converted to each joint of the osteotomy guide tool 4, the second moment received by each joint is obtained (see Figure 6 Specifically, the second moment can be understood as the compensation moment of each joint in each joint space obtained by multiplying the first moment by the transpose of the Jacobian matrix.

[0102] Step SB5: Apply the corresponding friction force feedforward fm to each joint of the osteotomy guide tool 4 to obtain a third torque at each joint. Specifically, the friction force feedforward fm can be calculated based on the velocity information of each joint fed back by the osteotomy guide tool 4. Applying the friction force feedforward fm to each joint of the osteotomy guide tool 4 can provide feedforward compensation for the joint torque.

[0103] Step SB6: Based on the theoretical output torque Fs, the third torque and the second torque, the driving information is obtained to realize the control of the osteotomy guide tool 4 (see Figure 6 Specifically, the joint torque of the osteotomy guide tool 4 consists of three parts: the first part is the theoretical output torque Fs, the second part is the second torque converted from the first torque, and the third part is the friction compensation of each joint (i.e., the third torque).

[0104] For preference, please refer to Figure 7 , which shows an impedance control physical model, and its corresponding schematic diagram is as follows Figure 8 shown. Figure 7 In the figure, M represents the mass of the physical model, the wavy line S on the right represents the spring, and D represents the damping; Figure 8 It is the expression of the transfer function in control theory, Md is equivalent to Figure 7 The quality parameter of the physical model in , Bd is equivalent to Figure 7 The damping coefficient of the physical model, Kd, is equivalent to Figure 7 The elastic coefficient of the spring in the physical model. Those skilled in the art can understand the above impedance control model based on the existing technology, and will not be described in detail here.

[0105] Furthermore, the input of the impedance control model includes the following steps:

[0106] Step SC1: Based on the equivalent moment F output by the force sensor 304 under the action of the external environmental force, the position change corresponding to the joint is calculated according to the admittance control 311; Figure 9 The schematic diagram of the admittance control 311 is shown, which is also the expression of the transfer function in control theory. Ms is equivalent to Figure 7 The quality parameter of the physical model in Bs is equivalent to Figure 7 The damping coefficient of the physical model, Ks, is equivalent to Figure 7 The elastic coefficient of the spring in the physical model. The meaning and calculation of the equivalent moment F can be referred to Example 1.

[0107] Step SC2: Based on the posture change, the posture difference between the actual posture of the osteotomy guide tool 4 and the command posture is calculated by kinematics correct solution 310.

[0108] Step SC3: Using the posture difference as the input of the impedance control model. Thus, the closer the osteotomy guide tool 4 is to the warning boundary, the greater the additional driving torque required to drive its joints, and the greater the external force required by the operator, thereby reducing the risk of misoperation during surgery.

[0109] In the above embodiment, the osteotomy guide tool 4 serves as the manipulation end. Since the osteotomy guide tool 4 has only three degrees of freedom, this facilitates the simplification of the kinematic and dynamic models, thereby facilitating the implementation of the inverse kinematic solution 301, the forward kinematic solution 310, and the dynamic calculation 305. However, in other embodiments, the robotic arm 2 may serve as the manipulation end, or the robotic arm 2 and the osteotomy guide tool 4 may be combined and considered the manipulation end. It will be appreciated that in other embodiments, the control method is not limited to application in knee replacement surgery.

[0110] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other. In addition, the different parts between the various embodiments can also be used in combination with each other, and the present invention is not limited to this.

[0111] In summary, in the surgical robot, surgical robot control method, surgical robot system, and readable storage medium provided by the present invention, the surgical robot includes a manipulator terminal, and the surgical robot control method includes: setting a safe zone and a warning boundary outside the safe zone based on edge information of the surgical object; and compensating the driving information applied by the surgical robot to the manipulator terminal based on a distance function between the current posture of the manipulator terminal and the warning boundary, in combination with first feedback information fed back by the manipulator terminal and second feedback information generated based on external environmental forces, so that after the manipulator terminal exceeds the range of the safe zone, the driving effect of the external environmental forces on the manipulator terminal is reduced, eliminated, or limited. In this configuration, by compensating the driving information applied to the manipulator terminal with the first feedback information and the second feedback information, the external environmental forces are reversely compensated to the driving joints, thereby achieving boundary control, minimizing the external environmental forces from acting on the patient. When the manipulator terminal exceeds the range of the safe zone, the greater the additional driving torque required to drive the joints of the robotic arm, the greater the required external environmental forces, thereby preventing operator misoperation.

[0112] The above description is only a description of the preferred embodiments of the present invention and does not limit the scope of the present invention. Any changes and modifications made by ordinary technicians in the field of the present invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A readable storage medium having a program stored thereon, which is used to control a surgical robot, wherein the surgical robot includes a manipulation end, characterized in that: When the program is executed, it achieves: Setting a safety zone and a warning boundary outside the safety zone according to edge information of the surgical object; Based on a distance function between the current posture of the manipulator terminal and the warning boundary, combined with first feedback information fed back by the manipulator terminal and second feedback information generated based on external environmental forces, the driving information applied by the surgical robot to the manipulator terminal is compensated, so that after the manipulator terminal exceeds the range of the safety zone, the driving influence of the external environmental forces on the manipulator terminal is reduced, eliminated or limited; The first feedback information includes command posture information of the joint of the manipulation terminal, and the second feedback information includes an impedance control model of the joint of the manipulation terminal caused by the external environmental force; The step of compensating the driving information applied by the surgical robot to the manipulation end comprises: The theoretical output torque Fs is calculated according to the command posture information; Based on the posture difference between the current posture of the manipulator terminal and the command posture, and the speed difference between the current speed of the manipulator terminal and the command speed, a first torque in Cartesian space is calculated according to the impedance control model; Transform the first moment into the second moment acting on each joint according to the transformation of the Jacobian matrix at the current joint angle; Feeding forward the corresponding friction force f to compensate each joint of the manipulator end to obtain the third torque of each joint; The driving information is obtained based on the theoretical output torque Fs, the third torque, and the second torque.

2. The readable storage medium according to claim 1, wherein The step of calculating the theoretical output torque Fs according to the command posture information includes: Obtaining a command angle θ of the joint of the manipulator terminal through kinematic inverse solution according to the command posture information Xd; The command angle θ is used as the input of the dynamics calculation to obtain the theoretical output torque Fs.

3. The readable storage medium according to claim 2, wherein: The input of the impedance control model includes the following steps: According to the equivalent moment F output by the force sensor under the action of the external environmental force, the position change corresponding to the joint is calculated according to the admittance control; Based on the posture change, a posture difference between the actual posture of the manipulator terminal and the command posture is calculated by kinematic forward solution; The posture difference is used as input to the impedance control model.

4. The readable storage medium according to claim 1, wherein The manipulation end includes a robotic arm and / or a manipulator, the first feedback information includes command posture information of the joints of the robotic arm and / or the manipulator, and the manipulator is used to fix and guide surgical instruments to perform surgical operations.

5. A surgical robot, characterized in that: The invention comprises a manipulation terminal and a readable storage medium according to any one of claims 1 to 4, wherein the manipulation terminal comprises a robotic arm and / or a manipulator for guiding a surgical instrument to perform a surgical operation, and the manipulation terminal is controlled when a program in the readable storage medium is executed.

6. A surgical robot system, characterized in that: It includes a control device, a navigation device, a manipulation terminal and a readable storage medium according to any one of claims 1 to 4, the navigation device is used to track the current posture of the manipulation terminal and feed back the posture information to the control device, and the control device controls the manipulation terminal according to the program of the readable storage medium.

7. The surgical robot system according to claim 6, wherein: The manipulation end includes a robotic arm and a manipulator for guiding surgical instruments to perform surgical operations, the manipulator has multiple degrees of freedom, and the first feedback information includes command posture information of the joints of the robotic arm and / or the manipulator.

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